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How to compile and run java files from sub-directory

I'm trying to compile .java files and store them in a sub-directory called bin. I then want to run the generated .class files from the main directory. How can I do this?
Here's my Makefile:
# java compiler
JCC = javac
# output directory
OUTDIR = bin/
# compilation flags
JFLAGS = -g -d $(OUTDIR)
# default target entry
default: A.class B.class C.class
A.class: A.java
$(JCC) $(JFLAGS) A.java
B.class: B.java
$(JCC) $(JFLAGS) B.java
C.class: C.java
$(JCC) $(JFLAGS) C.java
# To start over from scratch, type 'make clean'.
# Removes all .class files, so that the next make rebuilds them
clean:
$(RM) $(OUTDIR)*.class
What I want to do:
make
java bin/A

You must specify the bin directory as the classpath of the JVM, using the -cp option
java -cp bin A
A being the fully qualified name of the class to run.

Import multiple libraries in makefile within Javac command

The problem
This is a problem I just faced using makefile in java, on Windows.
I wanted to set up my classpath with multiple path (libraries, etc.). The new command work by hands, but not from the makefile which throws me this error :
javac : no source files
Example
Let's say I have this makefile :
JFLAGS = -g
JARFLAGS = -cvfm
CLASSPATH = ./bin
LIBS = C:/java/lib/mylib.jar
SOURCEPATH = ./src/client
compileAll:
javac $(JFLAGS) -d $(CLASSPATH) -cp $(CLASSPATH)\;$(LIBS) $(SOURCEPATH )/*.java
jar $(JARFLAGS) app.jar bin/client/MANIFEST.MF bin/client/*.class
So the command line to compile the project is :
javac -g -d ./bin -cp ./bin;C:/java/libs/lib.jar ./src/client/*.java
It works well.
The class files goes to ./bin directory. It imports classes from ./bin and the lib.jar library. And it compliles all the source files from the ./src/client directory.
This command works perfectly by hands, but no from the makefile which doesn't compile anything.

Thanks to my text editor which colored the ';' character, I understood that I just needed to escape (disable) the ';' character by using a '\' :
javac -g -d ./bin -cp ./bin\;C:/java/libs/lib.jar ./src/client/*.java
Now, it works well from makefile !

make file Java "missing operator" "none to do with default"

I am trying to build a make file for my program and Im getting the error missing operator at line 4 (javac $(JFLAGS)). I am also getting the error "none to do with default". Can someone help me with this error please? i have been stuck for quite a bit. Thank you much
JFLAGS = -g -d
JC = javac
%.class : %.java
javac $(JFLAGS)
CLASSES = \
Hello.java
default: $(CLASSES:.java=.class)
clean:
$(RM) *.class

You mention you are getting the error
make: Nothing to be done for 'default'.
This is not an error. It is make telling you that the target default is up to date and none of its prerequisites are older than it or need to be remade. For your particular case this will occur when the file Hello.class already exists in the same directory as your makefile. It is not an error but a simple message from make.
With regards to your other error
Java: missing operator at line 4
might this possibly say
makefile:4: *** missing separator. Stop.
instead? If that is the case then it means that you have not correctly indented the line
javac $(JFLAGS)
with a tab character.
Note: I mention this because it appears to be the closest error message to what you have described that I can replicate.
Another more pressing issue than the above is in particular your use of javac $(JFLAGS) and JFLAGS. In JFLAGS you have specified the -d option. When you execute javac $(JFLAGS) the error you get should look similar to
$ javac -g -d
javac: -d requires an argument
This is because the -d option when passed to javac is used to tell javac where the output directory that it should place .class files is. If you want your .class files to be output in the same directory as your makefile relative to their package name (see below) then you need to delete the -d option and declare JFLAGS as
JFLAGS = -g
If however, you dont want your .class files to be output in the same directory as your makefile then you need to declare a directory after the -d option in JFLAGS as
JFLAGS = -g -d /path/to/my/output/directory
Now that we've covered the -d option let's move on to actually compiling your .java files. The current rule you have is
%.class : %.java
javac $(JFLAGS)
this should to be altered to
%.class : %.java
$(JC) $(JFLAGS) $<
The automatic variable $< stands for the first prerequisite and will create a command like
$ javac -g Hello.java
for your particular example, which will create a Hello.class file in the same directory as the makefile and your Hello.java file.

Batch file to execute java program

I have multiple .java files inside a folder (e.g temp/code/project)
I want a batch file that will compile and run these java files.
The batch file should create class files inside the same structure where java files are located starting with the classes folder (i.e classes/temp/code/project)
I don't know how to write a batch file. Can any body help me with this? Thanks in advance.

Theoretically you should write the following:
#echo off
::compile classes
javac -cp YOUR_CLASSPATH com/yourcompany/YourClass1.java
javac -cp YOUR_CLASSPATH com/yourcompany/YourClass2.java
javac -cp YOUR_CLASSPATH com/yourcompany/YourClass3.java
javac -cp YOUR_CLASSPATH com/yourcompany/YourClassLauncher.java
:: create jar
jar cvfM Manifest.txt myjar.jar *.class
echo.
echo Hit any key to launch project.
pause
java -jar myjar.jar
pause
If you have one class that depends on all other classes in your project it is enough to run javac with this class only: compiler will compile everything.
# Manifest.txt
Manifest-Version: 1.0
Class-Path: .;MyUtils.jar
Created-By: 1.6.0
Main-Class: com.yourcompany.YourClassLauncher
This is only example and a good exercise. In real life people use special build tools like good old Ant, Maven or newer Graidle or Buildr. I'd recommend you to take one of them.

Something along the lines of
cd C:\temp\code\project
javac -classpath . -d C:\classes\temp\code\project\ *.java
You may not need to include the -classpath tag (I always do so that I don't have to worry about maintaining my CLASSPATH variable. The -d tag specifies a particular directory to place generated class files.

How can I compile and run a Java class in a different directory?

I'm writing a makefile that compiles a .java file in a different directory, and then I want to run it, without changing directories. I want to do something along the lines of:
$(SQM_JAVA_TOOL_DONE) : $(SQM_JAVA_TOOL)
$(shell cd /home_dir)
javac myjavafile.java
java myjavafile
where the Java file is /home/myjavafile.java, and the makefile isn't running from /home.
How can I do this?

I might be misunderstanding the question, but you can compile with
javac /home/MyJavaFile.java
This will create MyJavaFile.class in /home
You can then run it by including /home on the classpath. e.g.
java -cp /home MyJavaFile
If you want to generate the class file in a different directory then you can use the -d option to javac.

Use the -d command line parameter with javac to tell it what directory you'd like to store the compiled class files in. Then, to run the program, simply include this directory in the classpath:
javac -d some/directory myjavafile.java
java -cp some/directory myjavafile

Just to add to the existing answers, you may want the --source-path flag:
--source-path <path>, -sourcepath <path>
Specify where to find input source files
I believe this effectively sets the package root javac will compile from (i.e. <path> will be stripped from the expected package name of the files). It's still necessary to enumerate the files to compile, and this should still be relative to the current working directory, not the path passed to --source-path.
For example, to compile and run from a project's root where source is stored in src/ and you want it build in bin/:
$ javac --source-path src -d bin src/mypackage/*.java
$ java -cp bin mypackage.Main
This works even from directories elsewhere in the filesystem, e.g.:
$ javac --source-path /some/absolute/path/src -d /some/absolute/path/bin /some/absolute/path/
$ java -cp /some/absolute/path/bin mypackage.Main

I am using VS Code and installed java and code runner extensions. When I created new java project using the extension, it was creating the .class file in src instead of bin. To solve the issue I opened settings.json file from File > Preferences > Settings and searched for "settings" (or "code-runner"). Then I added following lines in that file.
"code-runner.executorMap": {
"java": "cd \"$workspaceRoot\\\" && javac --source-path src -d bin src\\$fileName && java -cp bin $fileNameWithoutExt",
}
If you don`t want to see the command that runs before code file then add these lines instead:
"code-runner.clearPreviousOutput": true,
"code-runner.showExecutionMessage": false,
"code-runner.executorMap": {
"java": "there is && clear added in the execution paramater"
"java": "cd \"$workspaceRoot\\\" && javac --source-path src -d bin src\\$fileName && clear && java -cp bin $fileNameWithoutExt",
}
I hope this finds someone with similar issue.